Adverse pregnancy outcomes are major public health problems, particularly in developing countries. The investigators reported that multivitamin supplements resulted in about 40 percent reductions in fetal loss, low birth weight, and severe preterm birth, and significantly improved the immune status of HIV positive pregnant women in Tanzania. The investigators state that ascertaining whether these results are generalizable to the much larger population of HIV negative women is a research priority of health officials in many developing countries and of senior officials at international organizations, and is the next priority of the investigators. They propose to study the efficacy of the supplements on these outcomes among 6000 consenting women. Women who are no more than 27 weeks pregnant will receive standard prenatal care and daily doses of one of two regimens between baseline and delivery: multivitamins including all B, C, E, A, folate, and iron OR vitamin A, folate, and iron supplements only. They will undertake a comprehensive assessment of diet among these women, and relate dietary intake to pregnancy outcomes. HIV infected women will receive multivitamins and will not be randomized. Each woman will be followed monthly until the 36th week of pregnancy and then once every week until delivery. Compliance will be examined by pill count and measurement of urine riboflavin and plasma ferritin levels in a random subsample. They will administer a food frequency questionnaire (FFQ) at randomization and at 36 weeks of gestation, and a 24 hour dietary recall at each monthly visit until 36 weeks of gestation. Research assistants will attend to women throughout the study. They will also study the effect of prenatal multivitamin supplements on infant mortality and growth. At three month intervals during infancy, they will measure maternal and infant dietary intake and anthropomorphic status. The associations of maternal dietary intake with infant mortality and growth will be examined controlling for breastfeeding, infectious morbidity, and other postpartum influences on infant health. To examine potential mechanisms of action of the supplements or dietary patterns and intake of individual nutrients, they will assess the following secondary outcomes among women: hemoglobin levels, T cell counts, and placental weight.